Coupling X-ray microtomography imaging and acoustic emission monitoring to unravel laboratory earthquakes: The KORE apparatus

Earthquakes initiate at 5-15 km depth and cannot be observed directly in situ. Therefore, laboratory experiments were developed in the past 50 years to reproduce and study laboratory earthquakes to unravel the mechanisms of rock deformation prior and during seismic slip. However, all experiments are limited by that fact that is it not possible to measure at the same time the seismic and aseismic components of deformation and image the interior of the samples as the microstructure evolves toward brittle failure. We have developed a new rock deformation apparatus, the KORE rig, installed on beamline ID19 at ESRF, which couples X-ray tomography and acoustic emission recording while reproducing conditions of temperature and stress at 10 km depth. We plan to rock deformation experiments using the KORE apparatus to elucidate the real-time fault propagation in 3D rock samples and so characterize the link between delocalized faulting, and slow and fast slip events.